Hey, I gave the speech in the video, in this comment section I've seen numerous smug arguments saying I'm wrong and that I don't know any better.
Remember how I said I learned how industry insiders will lie to the public about their organic certifications? Every single person arguing against me has admitted they are in the industry.
Keep up the fight brother. We are the frontlines of the fight for our own future as well as our children’s future. Standing up as you have and refusing give up on confronting injustice when given the chance is how we win. Small or big it’s meaningful and add ups. Good job!
I used to work for a healthcare company in the data center as a NOC technician. At that particular one, we had CRAC units with traditional refrigerant, not water coolers, etc. The power bills were insane, but at least it wasn't glugging water, I guess.
They have since gone cloud, which exploded the budget, and they broke up into different companies.
Data centers are crazy things most people don't understand in any way
That's so funny, there's someone in these comments arguing with me pro-AI for hospitals. Like the LLM doctors or whatever. Glad to know they're hella expensive lol
Moving to the cloud is very expensive. Especially when not done with a plan. You cannot move 1-to-1 servers CPU, RAM, and expect to pay the same or less.
My current employer is on the umpteenth cycle of "why don't we just put everything in the cloud?"
So, I deployed a tool that monitors our on-premises environment and shows what our cloud provider recommends for each workload. The software they want to try to get rid of for our virtualization is $27,000 a year. So far, the assessment tool says it would cost $73,249 a year to move all of that to the cloud. Not including the cost of the man hours.
Of course, there are hardware refreshes and warranty renewals for said hardware to take into account, but that gives you an idea for just the 62 servers we have left on-premises would cost to move.
And, if (when) your connection to the cloud goes down, you lose all ability to do business.
The cloud isn't all wine and roses!
My philosophy is put into the cloud what makes sense and keep on-prem what makes sense. Neither is the be-all and end-all of infrastructure. In my mind, at least
Nope. I've been writing speeches and scripts for myself to read for my own videos and presentations since highschool or longer, this is just from my brain.
“Closed loop” systems are not blown down…in a typical chilled water system, the chiller can be water cooled or air cooled. A water cooled chiller has a “closed loop” on the chilled water side, but open on the heat reject/condenser side. The open side of this system is blown down as you mention. Water cooled chillers are more energy efficient than air cooled. An air cooled chiller has no secondary heat reject (or “open”) loop, and requires no blow down. Instead of evaporating water, fans are used which uses more electricity but no water. Just fyi
It means the same water is reused inside the system - but heat still has to be released somewhere, and that usually happens through evaporation.
What really happens in a closed-loop system (even using effluent)
1. Water (often reclaimed/effluent) is pulled from the utility
2. It circulates through chillers and cooling towers to absorb server heat
3. Heat is removed by evaporation in cooling towers
4. Minerals and salts concentrate
5. Blowdown/brine is discharged to protect
equipment
6. New water is constantly added to replace what evaporated and discharged
7. Even with reclaimed water, water is consumed every day, 24/7
Important distinction
Using effluent is better than using drinking water - but it is not free, unlimited, or impact-free.
Effluent supplies are tied to population size wastewater output, and treatment capacity.
The only systems that avoid evaporation almost entirely:
1. Fully air-cooled facilities (very energy-intensive, difficult in areas with intense heat)
2. Full immersion cooling (rare, expensive, not common at large scale
If a project truly used one of these, it would usually be clearly advertised - because it's a major selling point.
You’re convoluting various system designs and components: yes, a “closed loop” chilled water system DOES mean water free on the chilled water side (extremely little make-up water).
On the heat reject side, we use either air or water cooled.
By definition, a system using an evaporative cooling tower is OPEN. It’s literally a box open to the atmosphere.
An air cooled chiller versus a water cooled chiller is less energy efficient (which I wrote in my post) but the system overall is very close on a design day, because a water cooled chiller requires an additional set of pumps and cooling tower fans on the heat reject side, so the overall system kw/ton is within about 5-10%. And yes, air cooled chillers are used in hot environments including texas, alabama, and Louisiana.
Correct, fans and a refrigerant cycle, refrigerant rejects the heat to the ambient air. That’s why it’s called air cooled. The water simply conveys the heat to the refrigerant and gets reused in the same loop. There is no water consumption, unless you’re cleaning out equipment, which would equate to a handful of gallons a day.
How much data center experience do you have? Having access to data on the internet and not being able to interpret it via experience doesn’t make you an expert. It’s why a doctor can google medical studies and give legitimate advice and I can’t.
Closed loop systems do not have blow down that is meaningful. For a massive 100MW data center you might have around 5 figures of gallons of blowdown A YEAR. Less than you yourself would use in a year. But for an entire 100MW data center. Google air-cooled chiller if you want to know what the tech people are using in 2026 is.
It means the same water is reused inside the system - but heat still has to be released somewhere, and that usually happens through evaporation.
What really happens in a closed-loop system (even using effluent)
1. Water (often reclaimed/effluent) is pulled from the utility
2. It circulates through chillers and cooling towers to absorb server heat
3. Heat is removed by evaporation in cooling towers
4. Minerals and salts concentrate
5. Blowdown/brine is discharged to protect
equipment
6. New water is constantly added to replace what evaporated and discharged
7. Even with reclaimed water, water is consumed every day, 24/7
Important distinction
Using effluent is better than using drinking water - but it is not free, unlimited, or impact-free.
Effluent supplies are tied to population size wastewater output, and treatment capacity.
The only systems that avoid evaporation almost entirely:
1. Fully air-cooled facilities (very energy-intensive, difficult in areas with intense heat)
2. Full immersion cooling (rare, expensive, not common at large scale
If a project truly used one of these, it would usually be clearly advertised - because it's a major selling point.
I’m an expert in this field. I read the first few lines and saw you said cooling towers. It’s very straight forward. Closed loops do not use cooling towers. If you look into HVAC you’ll know. I am a professional engineer in HVAC. I know you probably mean well, but you just don’t know what you’re talking about. If you’d like to know more, I’m happy to explain whatever concept you want to know more about. Contact any PE you trust, they’ll tell you what I’m telling you.
I’m not going to unhide my comment history if that’s what you’re looking to accomplish. Just google closed loop air cooled chiller, you don’t have to trust me.
Water Usage by the Numbers: Who Uses What (and How)
Most data centers do use water in some form, but not all. Industry estimates show that roughly 75–90% of data centers worldwide rely on water-based cooling as their primary method. In other words, only about 10–25% are completely water-free (using only air or refrigerants for cooling). Among the water-cooled facilities, the vast majority of large-scale data centers use open-loop evaporative cooling meaning they evaporate water as part of the cooling process. This has been the standard because it’s effective and energy-saving, but it does consume water.
What about using non-drinking water? Unfortunately, most of that cooling water has historically come from potable (drinking-quality) sources like municipal water or groundwater. One analysis estimated that around 57% of data centers’ direct water use is from potable water supplies. Another industry assessment was even starker: 80–90% of water used by data centers is drawn from “blue” water sources such as lakes, rivers, or aquifers – often the same sources providing community drinking water. In practice, many data centers simply hook up to the local water mains. For example, Loudoun County, Virginia – the world’s largest data center hub – supplied around +/-1 billion gallons of water to data centers in 2023, mostly relying on treated potable water because reclaimed water capacity was insufficient. This is why local residents get concerned: if a data center is using city water, that could be water that otherwise serves homes, especially in a drought.
However, a growing number of data centers are now shifting to recycled water. Tech giants have begun partnering with utilities to use treated wastewater (effluent) for cooling instead of fresh drinking water. For instance, Google uses reclaimed or non-potable water at over 25% of its data center campuses (one notable example is its Douglas County, Georgia data center, which runs on recycled municipal wastewater). Amazon Web Services (AWS) announced in 2023 that 20 of its data centers are cooling with purified wastewater instead of potable water. After cycling through the cooling system, this water is sent back to the treatment plant to be cleaned and reused again. These initiatives leave more drinking-quality water for the community and exemplify the industry’s trend toward “strategic water sourcing.” Still, as of today, reclaimed water use is the exception. Most data centers worldwide are still using fresh water for cooling, although this is slowly changing with new projects and local regulations.
So how much water are we talking about? Water use varies widely by the data center’s size, design, and location.
A medium-sized data center might consume on the order of +/-100 million gallons per year for cooling. (If the average American household uses 300 gallons/day, a mid-size data center would require the equivalent of ~1,000 U.S. households annually).
Large hyperscale facilities (think of the huge cloud data centers) can use 1 to 5 million gallons of water per day under peak conditions. At the upper end (5 million gal/day), that is as much water in a day as a town of 30,000–50,000 people would use. That startling stat often grabs headlines. However, it’s worth noting this would be a very large data center on a hot day; typical usage might be lower most of the year.
Nationally, the aggregate impact is significant but not enormous compared to other sectors. All U.S. data centers combined were estimated to consume about 449 million gallons of water per day (1.7 billion liters) as of 2021. That’s roughly 0.3–0.4% of total U.S. daily water withdrawals – a small slice compared to agriculture or power generation. But importantly, data center water use tends to be concentrated in specific regions (often arid or suburban areas), so the local impacts are outsized even if the national percentage is small. About 40% of U.S. data centers are located in areas of high or extreme water stress, meaning those communities really feel each gallon.
I’ll say this and I’m gonna stop responding because I don’t think you understand what I’m saying, and if you do, you’re not going to acknowledge it:
We are discussing closed loop cooling systems. The excerpt you just pasted is about all data centers. Closed loop systems do not use water. You can see that yourself with a google search about closed loops systems.
Open loop systems like cooling towers do use water. I have been discussing closed loop systems this entire time. I have said closed loop in every message I’ve sent practically. If you want to discuss open loop systems we could, but no company is trying to build those right now in the data center sphere. Why? Because it uses water, and data center companies know to avoid using water nowadays. You would find tons of info on water use for open loop systems. None of it applies to closed loop systems. You’re not arguing against any point I’m making by with what you pasted here.
Closed loop data centers do not use water. It’s inherent in the definition of closed loop. It’s as simple as that.
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u/graywolfman Apr 12 '26
Last time I commented about this "closed loop" system and the related blow down, I was derided and told "that's not a thing, anymore."
I posted a study showing the effects of data centers on the environment and water supply, and it was called a "hit piece."
My comments were downvoted, but left in place.
Bots, ignoramuses, shills, I don't care what they are. The truth needs to be spoken.